1. Field of the Invention
This invention relates to television cameras and more specifically, to automatic light control systems for such cameras.
2. Description of the Prior Art
In many instances, it is desirable to provide automatic light control systems for use with television cameras. Such systems are particularly advantageous for use with so-called low light level television cameras.
Presently known systems use a mechanical device for controlling the light level impinging on the face plate of the television camera. In many of the prior art devices, for instance, a motor driven iris is adjusted to compensate for changes in total scene illumination.
In other prior art devices, the position of a neutral density filter wedge is adjusted to compensate for changes in total scene illumination. Since either type of device requires continual adjustment during normal operation, friction and wear limit the performance characteristics and life of the system. Furthermore, since the presently known systems all function by changing the total incoming light level, a moving scene may produce smear during the frame time of the camera.